Identify MC33771C or MC33772C over SPI

[tbondar]

I'm writing firmware for a hardware design where either the 7 cell or the 14 cell version of the chip can be populated. I would like to handle both in the same firmware. Is there a way to ask the BCC chip to tell me which version it is? I've glossed through the datasheet but didn't find a register that would return a device ID or something similar. Thanks!

[TomasVaverka · Accepted solution]

Hello Tamás,

You are right, neither the MC33771C nor the MC33772C includes a dedicated identification register like WHO_AM_I. This means there is no simple or direct way to identify the BCC over SPI. Anyway, I guess you may try reading from a register that only exists or is valid on one of the BCCs. For example, read MEAS_CELL7 or higher. If the read returns valid data, the device is an MC33771C.

BRs, Tomas